JP2012082260A - Adhesive sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adhesive sheet which can prevent or eliminate air holes and blisters, and can restrain reduction of adhesive force even when used under an environment getting into contact with water.SOLUTION: The adhesive sheet 1 includes a substrate 11 and an adhesive layer 12. On the surface of the adhesive layer 12 where an adherend is to be pasted, there are provided a plurality of areas 2 where a group of grooves 21 are formed. Grooves 21 of one area 2 are not mutually communicated with grooves 21 of another area 2. A plurality of through-holes 3 penetrating from the surface of the substrate 11 to the grooves 21 of the adhesive layer 12 are formed in the adhesive sheet 1.

Description

  The present invention relates to an adhesive sheet that can prevent or remove air pockets and blisters.

  For adhesive sheets with large dimensions, such as decorative films, marking films, and glass shatterproof films, which are pasted on adherends such as windows, the adhesive sheet may have wrinkles when applied, or between the adherend and the adhesive surface. In some cases, air may be trapped and the appearance of the pressure-sensitive adhesive sheet may be impaired. In addition, since it is difficult to align the adhesive sheet with the adherend, it may be necessary to re-attach the adhesive sheet. In this case, the adhesive sheet may be torn, the adhesive sheet may be wrinkled, Problems such as lowering often occur.

  On the other hand, resin materials such as acrylic resin, ABS resin, polystyrene resin, and polycarbonate resin may generate gas when heated, but when an adhesive sheet is attached to an adherend made of such a resin material. The gas generated from the adherend causes blistering between the adherend and the adhesive sheet.

  In order to solve the above problems, a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer provided with a concave groove opening at an edge of the base sheet has been proposed (Patent Document 1). In this pressure-sensitive adhesive sheet, the grooves are in a lattice shape in plan view, and all are communicated with the edge of the pressure-sensitive adhesive sheet. According to this pressure-sensitive adhesive sheet, it is possible to prevent air accumulation or blistering of the pressure-sensitive adhesive sheet by drawing air on the pressure-sensitive adhesive surface side from the groove to the edge of the pressure-sensitive adhesive sheet.

International Publication WO2003 / 025078

  However, in the pressure-sensitive adhesive sheet of Patent Document 1, all the grooves are communicated with the edge of the pressure-sensitive adhesive sheet. Therefore, when the pressure-sensitive adhesive sheet is used in an environment where water contacts, When affixed to a kimono, there is a problem that water such as rainwater enters the entire surface of the pressure-sensitive adhesive sheet through the groove and causes a decrease in the adhesive strength.

  The present invention has been made in view of such a situation, and can prevent or remove air pockets and blisters, and even when used in an environment where water comes into contact, the adhesive force is reduced. It aims at providing the adhesive sheet which can suppress this.

  In order to achieve the above object, the present invention provides a pressure-sensitive adhesive sheet comprising a base material and a pressure-sensitive adhesive layer, and a region where a group of grooves is formed on the adherend-adhering surface of the pressure-sensitive adhesive layer. A plurality of the grooves in one region and the grooves in the other region do not communicate with each other, and the adhesive sheet penetrates from the surface of the base material to the groove of the adhesive layer. Provided is a pressure-sensitive adhesive sheet having a plurality of holes (Invention 1).

  In this specification, “sheet” includes the concept of film, and “film” includes the concept of sheet. In the present specification, the “surface of the substrate” refers to a surface of the substrate opposite to the surface in contact with the pressure-sensitive adhesive layer.

  According to the said invention (invention 1), an air pocket and a blister can be prevented or removed through a groove | channel and a through-hole, and the groove | channel of each area | region does not mutually communicate, The environment which water contacts Even when used underneath, a decrease in adhesive strength can be suppressed.

  In the said invention (invention 1), it is preferable that the width | variety of the said groove | channel is 30-500 micrometers, and the space | interval of the said adjacent grooves is 500-2000 micrometers (invention 2).

  In the said invention (invention 1 and 2), it is preferable that the space | interval of the said mutually adjacent area | regions is 2-30 mm (invention 3).

  In the said invention (invention 1-3), it is preferable that the planar view shape of the said area | region is a polygon (invention 4).

  In the said invention (invention 1-4), it is preferable that the length of the one direction of the said area | region and the length of the direction orthogonal to the said one direction are 25-120 mm, respectively (invention 5).

  In the said invention (invention 1-5), it is preferable that the said group of groove | channels in the said area | region is planar view lattice shape (invention 6).

  In the said invention (invention 1-6), it is preferable that the hole diameter of the said through-hole is 0.1-200 micrometers (invention 7).

In the above invention (invention 1 to 7), the pore density of the through holes is preferably 10 to 10,000 pieces / 100 cm ² (invention 8).

  In the said invention (invention 1-8), it is preferable that the said through-hole is formed by laser processing (invention 9).

  According to the pressure-sensitive adhesive sheet according to the present invention, it is possible to prevent or remove air pockets and blisters through the grooves and the through-holes, and because the grooves in each region are not in communication with each other, water is in contact with the environment. Even when used underneath, a decrease in adhesive strength can be suppressed.

It is sectional drawing of the adhesive sheet which concerns on one Embodiment of this invention. It is a reverse view of the adhesive sheet which concerns on the same embodiment. It is a figure which shows the arrangement | sequence of the through-hole formed in the Example.

Hereinafter, embodiments of the present invention will be described.
[Adhesive sheet]
FIG. 1 is a cross-sectional view of the pressure-sensitive adhesive sheet according to one embodiment of the present invention, and FIG. 2 is a back view of the pressure-sensitive adhesive sheet (in a state where the release material is peeled) according to the same embodiment.

  As shown in FIG. 1, the pressure-sensitive adhesive sheet 1 according to this embodiment is formed by laminating a base material 11, a pressure-sensitive adhesive layer 12, and a release material 13. However, the release material 13 is peeled off when the pressure-sensitive adhesive sheet 1 is used.

  As shown in FIG. 1 and FIG. 2, the adherend adherent surface (adhesive surface) of the adhesive layer 12 in the adhesive sheet 1 is provided with a plurality of regions 2 in which a group of grooves 21 are formed. The groove 21 in the region 2 and the groove 21 in the other region 2 do not communicate with each other. In addition, a plurality of through holes 3 penetrating from the surface of the base material 11 to the grooves 21 of the pressure-sensitive adhesive layer 12 are formed in the pressure-sensitive adhesive sheet 1.

The width W _{1 of the} groove 21 is preferably 30 to 500 μm, particularly preferably 40 to 100 μm. Since the width W _{1 of the} groove 21 is 30 μm or more, when the pressure-sensitive adhesive sheet 1 is pasted, the air between the adherend pasting surface of the pressure-sensitive adhesive layer 12 and the adherend is discharged through the groove 21. It is easy to be done and it becomes the thing excellent in the air release property. On the other hand, by the width W ₁ of the groove 21 is 500μm or less, to ensure the adhesion area to the adherend of the adhesive layer 12, it is possible to obtain a sufficient adhesive strength. Moreover, it can prevent that the base material 11 falls in the part of the groove | channel 21 after sticking, and impairs the external appearance of the adhesive sheet 1. FIG.

The width (hereinafter referred to as “adhesion width”) W ₂ of the adhesion region formed by the two adjacent grooves 21 is preferably 500 to 2000 μm, and particularly preferably 520 to 700 μm. By bonding the width W ₂ is 500μm or more, to ensure the adhesion area of the adhesive layer 12, it is possible to obtain a sufficient adhesive strength. On the other hand, by bonding the width W ₂ is less than 2000 .mu.m, to ensure the formation ratio of the groove 21, the deflation effect by the groove 21 can be sufficiently obtained.

  The depth D of the groove 21 is preferably 5 to 50 μm, particularly preferably 10 to 23 μm. Since the depth D of the groove 21 is 5 μm or more, when the pressure-sensitive adhesive sheet 1 is pasted, air between the adherend pasting surface of the pressure-sensitive adhesive layer 12 and the adherend is discharged through the groove 21. It is easy to be done and it becomes the thing excellent in the air release property. On the other hand, when the depth D of the groove 21 is 50 μm or less, it is possible to prevent the base material 11 from dropping at the portion of the groove 21 after application and deteriorating the appearance of the pressure-sensitive adhesive sheet 1.

  The cross-sectional shape (side view shape) of the groove 21 is not particularly limited, and may be, for example, a rectangle, a V shape, or a U shape.

  In the present embodiment, the group of grooves 21 constitutes the region 2. As shown in FIG. 2, the region 2 in the present embodiment is a quadrangle (square) in plan view, but is not limited thereto, and is an arbitrary polygon such as a triangle, hexagon, or octagon. It may be an arbitrary shape such as a circular shape, an elliptical shape, or an ∞ shape. However, considering the arrangement of the regions 2 and the distance between the regions 2, a polygon is preferable.

If the area 2 is square, one direction length _{L 2} of the direction (Y axis direction) perpendicular to the (X axis direction) of length _{L 1} and the one direction is preferably 25~120mm respectively, in particular It is preferable that it is 50-90 mm. If L ₁ and L ₂ are less than 25 mm, a region 2 without the through hole 3 may be generated. On the other hand, when L ₁ and L ₂ is more than 120 mm, after application of the pressure-sensitive adhesive sheet 1, when water intrudes into the groove 21 of the region 2 of the ends of the adhesive sheet 1, the penetration area is relatively large, the pressure-sensitive adhesive There exists a possibility that the adhesive force as the whole sheet | seat 1 may fall.

The width (hereinafter referred to as “barrier width”) W ₃ of the barrier formed by the adjacent regions 2 is preferably 2 to 30 mm, and particularly preferably 5 to 20 mm. When the barrier width W ₃ is 2 mm or more, even when water enters the groove 21 of the one region 2 after the adhesive sheet 1 is pasted, the water moves from the one region 2 to the adjacent region 2. This can be reliably prevented, and water can be prevented from spreading across the entire surface of the pressure-sensitive adhesive sheet 1 and reducing the adhesive force. On the other hand, it is the barrier width W ₃ is 30mm or less, the pressure-sensitive adhesive sheet 1 when stuck, the region of the air next to the from one region 2 between the adhesive surface and adherend of the adhesive layer 12 2 Accordingly, in combination with an air escape effect by a through-hole 3 to be described later, it is possible to effectively prevent or remove air accumulation when the pressure-sensitive adhesive sheet 1 is applied.

  In the present embodiment, the group of grooves 21 formed in the region 2 has a lattice shape in plan view, but is not limited thereto, and is not limited to this, for example, any one direction (for example, the X-axis direction and the Y-axis direction). Etc.) may be a straight line extending in parallel to each other, a curved line having an arbitrary shape, or an arbitrarily branched shape. However, in consideration of forming through holes 3 to be described later in accordance with the positions of the grooves 21, the group of grooves 21 is preferably arranged regularly, and particularly in a plan view lattice shape. preferable. When the group of grooves 21 are in a lattice shape in plan view, there is an advantage that when the adhesive sheet 1 is applied, the air between the adhesive surface of the adhesive layer 12 and the adherend becomes particularly easy to escape.

  In addition, although it is preferable that the groove | channel 21 of the adhesive layer 12 is not opening in the edge part of the adhesive sheet 1, you may open. If the groove 21 is not open at the end of the pressure-sensitive adhesive sheet 1, it is possible to effectively prevent water from entering the groove 21 after the pressure-sensitive adhesive sheet 1 is pasted. Moreover, even if the groove | channel 21 has opened in the edge part of the adhesive sheet 1, and water infiltrates into the groove | channel 21 from the opening part after sticking of the adhesive sheet 1, the water stays only in the area | region 2 of the said groove | channel 21, Since water does not migrate to the other region 2, it is suppressed that the infiltrated water reaches the entire surface of the pressure-sensitive adhesive sheet 1 and the adhesive force is reduced.

  The through holes 3 penetrate from the surface of the base material 11 to the grooves 21 of the pressure-sensitive adhesive layer 12, but it is not necessary that all the through holes 3 communicate with the grooves 21, and some of the through holes 3 are The surface of the substrate 11 may communicate with the adherend pasting surface between the groove 21 and the groove 21 or the adherend pasting surface between the region 2 and the region 2. Further, the through-hole 3 does not have to be completely located at the center of each groove 21, and only needs to communicate with at least the end of the groove 21. The arrangement of the through holes 3 can take an arbitrary shape such as a straight line or a curved line. Moreover, arrangement | sequences may cross | intersect like a lattice pattern, and a parallel straight line and zigzag form may be sufficient.

  The hole diameter of the through-hole 3 is preferably 0.1 to 200 μm through the base material 11 and the pressure-sensitive adhesive layer 12 (at all positions in the thickness direction of the base material 11 and the pressure-sensitive adhesive layer 12), particularly preferably It is preferable that it is 5-150 micrometers. When the hole diameter of the through-hole 3 is 0.1 μm or more, air or gas can easily escape through the through-hole 3. On the other hand, when the diameter of the through-hole 3 is 200 μm or less, the through-hole 3 is not noticeable and can prevent the appearance of the pressure-sensitive adhesive sheet from being impaired, and the mechanical strength of the pressure-sensitive adhesive sheet 1 can be maintained. It is. In particular, when it is required that the through hole 3 is not visible even at a close distance, the hole diameter on the surface of the substrate 11 is preferably 0.1 to 42 μm, particularly preferably 0.1 to 40 μm.

  The hole diameter of the through-hole 3 may be constant in the thickness direction of the pressure-sensitive adhesive sheet 1 or may be changed in the thickness direction of the pressure-sensitive adhesive sheet 1, but from the adherend pasting surface of the pressure-sensitive adhesive layer 12. It is preferable that the thickness gradually decreases over the surface of the substrate 11. Thus, by changing the hole diameter of the through-hole 3, not only the appearance of the pressure-sensitive adhesive sheet 1 can be kept good, but also water can be prevented from entering from the through-hole 3 after application.

The hole density of the through holes 3 is preferably 10 to 10,000 / 100 cm ² , and more preferably 50 to 5,000 / 100 cm ² . When the hole density of the through-holes 3 is 10 pieces / 100 cm ² or more, the through-holes 3 communicate with the grooves 21 in the region 2 and air or gas can easily escape. On the other hand, when the hole density of the through holes 3 is 50,000 / 100 cm ² or less, it is possible to prevent the tensile strength and tear strength of the pressure-sensitive adhesive sheet 1 from being lowered. In the present embodiment, when the pressure-sensitive adhesive sheet 1 is applied, air can be extracted not only from the through hole 3 but also from the groove 21 of the pressure-sensitive adhesive layer 12. The hole density of the through holes 3 can be reduced, that is, the number of the through holes 3 can be reduced, whereby the productivity of the pressure-sensitive adhesive sheet 1 can be improved.

  The through hole 3 is preferably formed by laser processing. According to laser processing, a through hole that satisfies the above-described conditions can be easily formed. However, the formation method of the through-hole 3 is not limited to this, For example, you may form by a water jet, a micro drill, a precision press, a hot needle, a molten hole, etc.

The type of laser used for laser processing is not particularly limited. For example, carbon dioxide (CO ₂ ) laser, TEA-CO ₂ laser, YAG laser, UV-YAG laser, excimer laser, semiconductor laser, YVO ₄ laser A YLF laser, a femtosecond laser, or the like can be used.

  In addition, although the through-hole 3 in the adhesive sheet 1 which concerns on this embodiment penetrates from the surface of the base material 11 to the groove | channel 21 of the adhesive layer 12, it may also penetrate the peeling material 13. .

  The material of the base material 11 is not particularly limited as long as it is a material that can form the through-hole 3. For example, a resin film, a metal film, a resin film on which a metal is deposited, paper, a laminate thereof, and the like Is mentioned. When the base material 11 consists of a resin film, the base material 11 may be opaque or transparent, but generally the through hole 3 is less noticeable when the base material 11 is opaque.

  Examples of the resin film include polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate and polybutylene terephthalate, polyvinyl chloride, polystyrene, polyurethane, polycarbonate, polyamide, polyimide, poly (meth) acrylate, polybutene, polybutadiene, Consists of resins such as polymethylpentene, acrylic urethane, ethylene vinyl acetate copolymer, ethylene (meth) acrylic acid copolymer, ethylene (meth) acrylic acid ester copolymer, ABS resin, ionomer resin, and various thermoplastic elastomers. A film, a foamed film, or a laminated film thereof, synthetic paper, or the like can be used. The resin film may be a stretched film, an unstretched film, or a film formed by a casting method using a process material. Further, as the paper, for example, high-quality paper, glassine paper, coated paper, laminated paper and the like can be used.

  In addition, the said resin film may contain various additives, such as an inorganic filler, an organic filler, and an ultraviolet absorber. In addition, as long as the shape of the through hole 3 is not adversely affected, a decorative layer is formed on the surface of the resin film by a method such as printing, printing, application of a paint, transfer from a transfer sheet, vapor deposition, sputtering, or the like. Or a coating layer such as an easy-adhesion coat or a gloss adjustment coat for forming such a decorative layer, a hard coat, a stain-proof coat, a surface roughness and a specular gloss. A coat layer such as a coat for adjustment and a coat for imparting weather resistance may be formed. Moreover, these decoration layers or coat layers may be formed on the whole surface of the said material, and may be formed partially.

  Among the above, a film made of polyvinyl chloride is preferable from the viewpoint of excellent curved surface followability. Moreover, when forming a decoration layer by printing, the film which consists of polyvinyl chloride is preferable also from the point which is excellent in a weather resistance and the fixing property of an ink.

  Although the thickness of the base material 11 is 1-500 micrometers normally, Preferably it is about 25-200 micrometers, but can be suitably changed according to the use of the adhesive sheet 1. FIG.

  The type of the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer 12 is not particularly limited as long as the groove 21 and the through hole 3 can be formed. Acrylic, polyester-based, polyurethane-based, rubber-based, silicone-based Any of these may be used. The pressure-sensitive adhesive may be any of an emulsion type, a solvent type, or a solventless type, and may be a crosslinked type or a non-crosslinked type.

  The thickness of the pressure-sensitive adhesive layer 12 is usually 1 to 300 μm, preferably about 10 to 50 μm, but can be appropriately changed depending on the application of the pressure-sensitive adhesive sheet 1.

  The material of the release material 13 is not particularly limited, for example, a film made of a resin such as polyethylene terephthalate, polypropylene, polyethylene, or a foamed film thereof, or paper such as glassine paper, coated paper, laminated paper, A silicone-based, fluorine-based, or long-chain alkyl group-containing carbamate or other release agent can be used.

  The thickness of the release material 13 is usually about 10 to 250 μm, preferably about 20 to 200 μm. Further, the thickness of the release agent in the release material 23 is usually 0.05 to 5 μm, preferably 0.1 to 3 μm.

  In addition, although the adhesive sheet 1 which concerns on this embodiment is provided with the peeling material 13, this invention is not limited to this, The peeling material 13 does not need to be. Furthermore, the magnitude | size, shape, etc. of the adhesive sheet 1 which concern on this embodiment are not specifically limited. For example, the pressure-sensitive adhesive sheet 1 may be a tape-shaped material (adhesive tape) composed of only the base material 11 and the pressure-sensitive adhesive layer 12 and may be wound into a roll shape to be a wound body.

[Manufacture of adhesive sheet]
As a method of forming a groove in the pressure-sensitive adhesive layer 12 in the pressure-sensitive adhesive sheet 1 according to the embodiment, for example,
(1) A method of directly providing the pressure-sensitive adhesive layer 12 having the grooves 21 on one surface of the substrate 11 using a comb blade or the like,
(2) After directly providing the flat pressure-sensitive adhesive layer 12 on one surface of the substrate 11, the pressure-sensitive adhesive layer 12 is brought into contact with an embossed roll having irregularities, and the grooves 21 are transferred to the pressure-sensitive adhesive layer 12. how to,
(3) A method of forming a pressure-sensitive adhesive layer 12 after providing unevenness on the base material for the release material 13 in advance and performing a release treatment on the uneven surface, and transferring the groove 21 to the pressure-sensitive adhesive layer 12,
(4) Method of forming unevenness on the release treatment surface of the release material 13 in advance, forming the adhesive layer 12 on the release treatment surface, and transferring the groove 21 to the adhesive layer 12 (see FIG. 1)
Among these, the method (4) is preferable from the viewpoint of operability and the like.
Hereinafter, the manufacturing method of the adhesive sheet 1 using the method of (4) is demonstrated.

  First, an embossing roll having a pattern of the groove 21 and the region 2 to be formed in the pressure-sensitive adhesive layer 12 is prepared, the embossing roll is pressed against the release treatment surface of the release material 13, and the release treatment surface of the release material 13 is touched with the above Transfer the pattern.

  Next, the pressure-sensitive adhesive layer 12 is formed on the release treatment surface of the release material 13 to which the pattern is transferred, and the pattern of the groove 21 and the region 2 is transferred to the pressure-sensitive adhesive layer 12. In order to form the pressure-sensitive adhesive layer 12, a pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer 12 and, if desired, a coating agent further containing a solvent are prepared, and a roll coater, a knife coater, a roll knife coater, an air knife coater, and a die coater. What is necessary is just to apply | coat and dry to the peeling process surface of the peeling material 13 with coating machines, such as a bar coater, a gravure coater, and a curtain coater.

  Next, the base material 11 is pressure-bonded to the surface of the pressure-sensitive adhesive layer 12 to obtain a laminate composed of the base material 11, the pressure-sensitive adhesive layer 12, and the release material 13.

  And the through-hole 3 which penetrates from the surface of the base material 11 to the groove | channel 21 of the adhesive layer 12 is formed. As described above, this through hole 3 is preferably formed by laser processing. The laser beam may be irradiated from the surface side of the substrate 11, may be irradiated from the release material 13 side, or may be irradiated directly to the exposed pressure-sensitive adhesive layer 12 after peeling the release material 13. Good. Moreover, when performing laser processing, you may move the adhesive sheet 1 to a plane direction suitably, or may incline so that a laser beam may be irradiated to the position of the groove | channel 21 of the adhesive layer 12. FIG.

  In the above manufacturing method, the pressure-sensitive adhesive layer 12 is applied and formed on the release material 13, and the formed pressure-sensitive adhesive layer 12 and the base material 11 are bonded together. However, the present invention is not limited to this. After the pressure-sensitive adhesive layer 12 is applied and formed on the substrate 11, the release treatment surface of the release material 13 may be pressure-bonded to the pressure-sensitive adhesive layer 12.

[Use of adhesive sheet]
When sticking the pressure-sensitive adhesive sheet 1 to an adherend, first, the release material 13 is peeled from the pressure-sensitive adhesive layer 12.

  Next, the adhesive sheet 1 is gradually pressed against the adherend from one end so that the exposed adhesive surface of the adhesive layer 12 is brought into close contact with the adherend. At this time, air between the adherend and the pressure-sensitive adhesive surface of the pressure-sensitive adhesive layer 12 passes through the groove 21 of the pressure-sensitive adhesive layer 12 and is discharged in a direction in which the pressure-sensitive adhesive layer 12 is not yet in close contact with the adherend. The Furthermore, the air existing in the groove 21 of the pressure-sensitive adhesive layer 12 escapes to the outside of the surface of the substrate 11 through the through hole 3. Therefore, it is difficult for air to be caught between the adherend and the pressure-sensitive adhesive surface of the pressure-sensitive adhesive layer 12, thereby preventing air from being trapped. Even if air is trapped due to air entrainment, the air is re-pressurized around the air reservoir portion or the air reservoir portion including the air reservoir portion, so that the air is outside the surface of the substrate 11 from the through hole 3. The air pocket disappears.

  In addition, even if gas is generated from the adherend after the adhesive sheet 1 has been attached to the adherend, the gas escapes from the through-hole 3 formed in the adhesive sheet 1 to the outside of the surface of the substrate 11, It is prevented that blisters are generated in the pressure-sensitive adhesive sheet 1.

  Here, even when water enters the groove 21 of the one region 2 after the adhesive sheet 1 is attached to the adherend, the groove 21 of the one region 2 and the groove 21 of the other region 2 communicate with each other. Therefore, it is possible to prevent water from transferring from the one region 2 to the other region 2, thereby suppressing water from reaching the entire surface of the pressure-sensitive adhesive sheet 1 and reducing the adhesive force.

  EXAMPLES Hereinafter, although an Example etc. demonstrate this invention further more concretely, the scope of the present invention is not limited to these Examples etc.

[Example 1]
An embossing roll having a grid-like groove and a square area pattern as shown in FIG. 1 (sectional view) and FIG. 2 (plan view) was prepared. The embossing roll is applied to the release-treated surface of a release material (Lintec Co., Ltd., KP-64 white, thickness: 80 μm) obtained by laminating one surface of high-quality paper with polyethylene resin, and then removing the laminate surface with a silicone release agent. The pattern was transferred to the release treatment surface of the release material by pressure contact.

  Next, an acrylic solvent adhesive (PA-10, PA-10) coating agent is applied to the release treatment surface of the release material onto which the above pattern has been transferred by a knife coater so that the thickness after drying becomes 26 μm. And dried at 90 ° C. for 1 minute. A transparent polyester film base material (manufactured by Toray Industries, Inc., thickness: 50 μm) was pressure-bonded to the pressure-sensitive adhesive layer thus formed to obtain a laminate having a three-layer structure.

The pattern of the groove | channel and area | region formed in the peeling material was transcribe | transferred to the obtained adhesive layer. The width W _{1 of} the groove formed in this pressure-sensitive adhesive layer was 60 μm, the adhesion width W ₂ was 550 μm, and the depth D of the groove was 18 μm. The size L ₁ × L ₂ of _one region was 70 mm × 70 mm, and the barrier width W ₃ was 15 mm.

Next, the laminate was irradiated with CO ₂ laser light from the substrate surface side to form through holes in an arrangement as shown in FIG. 3, and this was used as an adhesive sheet. Specifically, in plan view, units arranged in a straight line with 26 holes are formed in a zigzag shape in the width direction of the pressure-sensitive adhesive sheet, and the units are grouped together in the length direction of the pressure-sensitive adhesive sheet. It formed repeatedly so that it might not overlap. The length of the units arranged in a straight line is 50 mm, the distance between holes in the unit is 2 mm, and the distance between holes at the end in the longitudinal direction of the group (distance in the width direction of the adhesive sheet) is from 3 mm and 10 mm intervals. Ten types of adhesive sheets (3 mm / 10 mm, 20 mm, 30 mm, 40 mm, 50 mm, 60 mm, 70 mm, 80 mm, 90 mm, 100 mm) were prepared up to 3 mm and 100 mm intervals. In addition, inclination | tilt angle (theta) with respect to the adhesive sheet length direction of the unit located in a line was 7 degrees.

  The formed through hole had a hole diameter of about 50 μm on the substrate surface and a hole diameter of about 30 μm on the adhesive surface. The hole diameter of the through hole was measured using a scanning electron microscope (manufactured by Hitachi, Ltd., type S-2360N). In addition, although the hole penetrated the base material and the pressure-sensitive adhesive layer by laser processing, the release material did not penetrate.

[Comparative Example 1]
In FIG. 2, an embossing roll having a lattice-like groove pattern on the entire surface and having no barrier between regions (W ₃ = 0 mm) was prepared. The embossing roll is applied to the release-treated surface of a release material (Lintec Co., Ltd., KP-64 white, thickness: 80 μm) obtained by laminating one surface of high-quality paper with polyethylene resin, and then removing the laminate surface with a silicone release agent. The pattern was transferred to the release surface of the release material 13 by pressure contact.

A pressure-sensitive adhesive sheet was produced in the same manner as in Example 1 except that the obtained release material was used. The adhesive width W ₁ of the groove formed in the adhesive layer of the sheet is 60 [mu] m, the adhesion width W ₂ is 550 .mu.m, the depth D of the groove is 18 [mu] m, the entire surface of the adherend sticking face of the groove is pressure-sensitive adhesive layer Formed.

[Comparative Example 2]
Using a release material (Lintec Corp., KP-64 white, thickness: 80 μm) with one side of fine paper laminated with polyethylene resin and the laminate surface peeled off with a silicone release agent. A pressure-sensitive adhesive sheet was produced in the same manner as in Example 1 except that. Therefore, although this adhesive sheet has a through-hole, a groove was not formed in the adhesive layer.

[Comparative Example 3]
Without irradiating the laminated body of the three-layer structure obtained in Example 1 with laser light, the laminated body was used as an adhesive sheet as it was.

[Test example]
(1) Air escape test The air release test was performed as follows on the pressure-sensitive adhesive sheets obtained in Examples and Comparative Examples. The results are shown in Table 1.

  The pressure-sensitive adhesive sheet (size: 50 mm × 50 mm) from which the release material has been peeled is applied to a 70 mm × 70 mm melamine coated plate having a partial spherical recess (recess) with a diameter of 15 mm and a maximum depth of 1 mm (recess and pressure-sensitive adhesive sheet). The pressure-sensitive adhesive sheet is pressure-bonded (a squeegee is used depending on the case), and it is confirmed whether the air can be retained or whether the air can be removed. As a result, the pressure-sensitive adhesive sheet follows the concave part of the melamine-coated plate even if it is not pressure-bonded with the squeegee, and the pressure-sensitive adhesive sheet follows the concave part of the melamine-coated plate by pressure bonding with the squeegee. ○: air pressure is removed from the pressure-sensitive adhesive sheet by pressing several times with a squeegee, and the pressure-sensitive adhesive sheet follows the concave portion of the melamine-coated plate. The case where the air pocket was not removed without following the concave portion of the paint plate (including the remaining air even if the air pocket is small) is represented by x.

(2) Water-resistant adhesive strength test With respect to the pressure-sensitive adhesive sheets obtained in the examples and comparative examples (the pressure-sensitive adhesive sheets of Example 1 and Comparative Examples 1 and 2 are limited to those having a distance between holes of 10 mm), the water resistance is as follows. An adhesion test was performed. The results are shown in Table 1.

  After the pressure-sensitive adhesive sheet was prepared, the pressure-sensitive adhesive sheet was cut to 25 mm × 300 mm under an environment of 23 ° C. and 50% RH, and this test piece was attached to a stainless steel plate (SUS360) as an adherend. This was left to stand for one day in an environment of 23 ° C. and 50% RH, then immersed in warm water of 40 ° C. for one week, and taken out in an environment of 23 ° C. and 50% RH. It was. Further, as a comparison, the test sample 2 was set to stand for 1 week in an environment of 23 ° C. and 50% RH without being immersed in warm water.

  About the said test samples 1 and 2, the adhesive force by 180 degree peeling method (tensile speed 300m / min) was measured based on JISZ0237 (2000).

  As can be seen from Table 1, the pressure-sensitive adhesive sheet obtained in Example 1 was excellent in air bleeding and water-resistant adhesive strength. On the other hand, the pressure-sensitive adhesive sheet obtained in Comparative Example 1 was excellent in air bleeding but poor in water-resistant adhesive strength. In addition, the pressure-sensitive adhesive sheets obtained in Comparative Examples 2 and 3 had no problem with water-resistant adhesive strength, but were inferior in air bleeding.

  The pressure-sensitive adhesive sheet of the present invention is generally used when air accumulation or blistering is likely to occur in the pressure-sensitive adhesive sheet, for example, when the area of the pressure-sensitive adhesive sheet is large or when gas is generated from the adherend. It can be preferably used when a good adhesive force is required even in an environment where it contacts.

DESCRIPTION OF SYMBOLS 1 ... Adhesive sheet 11 ... Base material 12 ... Adhesive layer 13 ... Release material 2 ... Area | region 21 ... Groove 3 ... Through-hole

Claims (9)

A pressure-sensitive adhesive sheet comprising a base material and a pressure-sensitive adhesive layer,
On the adherend pasting surface of the pressure-sensitive adhesive layer, a plurality of regions in which a group of grooves are formed are provided,
The groove in the one region and the groove in the other region do not communicate with each other,
In the pressure-sensitive adhesive sheet, a plurality of through-holes penetrating from the surface of the base material to the groove of the pressure-sensitive adhesive layer are formed. The groove has a width of 30 to 500 μm,
The pressure-sensitive adhesive sheet according to claim 1, wherein an interval between the adjacent grooves is 500 to 2000 μm.   The pressure-sensitive adhesive sheet according to claim 1 or 2, wherein an interval between the adjacent regions is 2 to 30 mm.   The pressure-sensitive adhesive sheet according to any one of claims 1 to 3, wherein the planar view shape of the region is a polygon.   The pressure-sensitive adhesive sheet according to any one of claims 1 to 4, wherein a length in one direction of the region and a length in a direction orthogonal to the one direction are 25 to 120 mm, respectively.   The pressure-sensitive adhesive sheet according to any one of claims 1 to 5, wherein the group of grooves in the region has a lattice shape in plan view.   The pressure-sensitive adhesive sheet according to any one of claims 1 to 6, wherein the through-hole has a diameter of 0.1 to 200 µm. The pressure-sensitive adhesive sheet according to any one of claims 1 to 7, wherein a hole density of the through holes is 10 to 10,000 pieces / 100 cm ² .   The pressure-sensitive adhesive sheet according to claim 1, wherein the through hole is formed by laser processing.

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